Kentucky Bluegrass
Poa pratensis · Cool-season, perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Fairways
Variety / Cultivar
'Midnight' or similar dark green turf-type cultivars
Hardiness Zones
USDA Hardiness Zones 3-7, thrives in cooler northern climates, excellent cold tolerance, goes dormant and turns brown under extreme summer heat.
About This Grass
Forms a dense, high-quality turf with medium-fine texture and rich dark green to blue-green color. Mown height typically 1.5 to 2.5 inches, unmowed can reach 18-24 inches with open, pyramidal panicle seed heads.
Blade Characteristics
Blades are medium-narrow (2-4mm), flat to folded with prominent parallel veins and characteristic boat-shaped tips. Vernation is folded in the bud. Ligule is short and membranous; auricles are absent.
Root System
Moderate to deep fibrous root system with extensive underground rhizomes. Moderate establishment speed, forms a very dense thatch layer if not properly managed, excellent wear recovery.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized and cultivated across North America and temperate regions worldwide
Growth Habit
Aggressively rhizomatous, spreading underground to form a dense, uniform sod
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily), moderate to high water needs, enters summer dormancy during severe drought, prefers well-drained fertile soils with a pH of 6.0-7.0.
Mowing & Maintenance
Mowing height 1.5 to 2.5 inches. High maintenance level requiring regular fertilization (3-4 lbs N per 1000 sq ft annually), frequent irrigation, and periodic dethatching and aeration.
Special Characteristics
Excellent traffic and wear tolerance due to rhizomatous recovery, moderate shade tolerance compared to fescues, good winter color retention in milder zones, excellent erosion control.
Ecological Information
Introduced species in North America, provides good soil stabilization and erosion control, often blended with Perennial Ryegrass and Fine Fescues for home lawn seed mixes.